A side-by-side of Claude and OpenAI API prices by tier, what a month of usage costs at three workload sizes, and the modifiers that move the real bill.
*Published November 2, 2026. Pricing last verified: November 2, 2026, from each provider's own published pricing page.*
At list price, the Claude API and the OpenAI API cost the same per token at the premium, balanced and budget tiers as of November 2, 2026: $10/$50, $2/$10 and $0.10/$0.50 per million input/output tokens. The bills diverge on caching rates, long-context rules, tool fees and how each model counts tokens.
This guide puts the two current lineups in one table, prices a month of usage at three sizes, and walks through the modifiers a finance lead should model before signing off on a budget.
How much does the Claude API cost compared to the OpenAI API?
On Anthropic API pricing, Claude Sonnet 5.5 and gpt-6.1-sol both list at $2 per million input tokens and $10 per million output tokens as of November 2, 2026. Claude Fable 5.1 and gpt-6-astra both list at $10 and $50. Claude Haiku 5.5 and gpt-6-luna both list at $0.10 and $0.50.
Within the current generations, each provider has one model the other does not match on price: Claude Opus 5.5 at $4/$20, and gpt-6.1-terra at $1/$5. Older-generation models on both pricing pages sit at those same prices.
So the honest answer is "about the same per token, different per month." Which one ends up cheaper depends on your prompt lengths, how much of each prompt repeats, and which tools you call.
Claude vs OpenAI API pricing table
Pricing last verified: November 2, 2026, from each provider's own published pricing page. Standard (on-demand) pricing, USD per 1 million tokens. OpenAI prices are its short-context rates (272K input tokens or fewer).
| Tier | Claude model | Claude input / output | OpenAI model | OpenAI input / output |
| Premium | Claude Fable 5.1 | $10 / $50 | gpt-6-astra | $10.00 / $50.00 |
| Upper-mid | Claude Opus 5.5 | $4 / $20 | No gpt-6 model at this price | n/a |
| Balanced | Claude Sonnet 5.5 | $2 / $10 | gpt-6.1-sol | $2.00 / $10.00 |
| Lower-mid | No Claude 5.x model at this price | n/a | gpt-6.1-terra | $1.00 / $5.00 |
| Budget | Claude Haiku 5.5 | $0.10 / $0.50 | gpt-6-luna | $0.10 / $0.50 |
Claude Haiku 5.5 price applies to prompts up to 100,000 tokens; longer prompts are covered under Long context below.
Read the table row by row. The tiers are a Rho grouping by list price, not provider labels and not a quality verdict: two models in the same row cost the same, but they are not interchangeable on every task. Test both on your own prompts before you lock a budget to either one.
Two naming notes. Anthropic's page prints display names; OpenAI's pricing table prints lowercase model IDs, so both are reproduced exactly as listed. OpenAI also lists gpt-6-sol at the same $2.00/$10.00 as gpt-6.1-sol, but with a higher cached-input rate ($0.20 vs $0.10), so check which one your code actually calls.
Sources: Anthropic Claude pricing and OpenAI API pricing, both read November 2, 2026.
What a month of API usage costs at three workload sizes
The math is simple: millions of input tokens times the input price, plus millions of output tokens times the output price. For the medium workload on the balanced tier, that is 100 x $2 + 20 x $10 = $400 a month on either provider.
| Monthly workload (input / output) | Premium: Claude Fable 5.1 or gpt-6-astra | Balanced: Claude Sonnet 5.5 or gpt-6.1-sol | Budget: Claude Haiku 5.5 or gpt-6-luna |
| Small: 10M / 2M tokens | $200 | $40 | $2 |
| Medium: 100M / 20M tokens | $2,000 | $400 | $20 |
| Large: 1B / 200M tokens | $20,000 | $4,000 | $200 |
Each cell is the same for both providers, because the list prices match. Within the current generations, the two unmatched models land in between: Claude Opus 5.5 costs $80, $800 and $8,000 at the three sizes, and gpt-6.1-terra costs $20, $200 and $2,000.
These figures assume standard pricing, no caching, no tools, Claude Haiku 5.5 prompts of 100,000 tokens or fewer, and OpenAI prompts of 272K input tokens or fewer. Compare tiers like for like, then adjust for the modifiers below.
Why Claude and OpenAI API bills differ from list price: caching, batch, long context and tools
The Claude API and the OpenAI API match on list price at three tiers, but six modifiers decide whether the invoice matches: prompt caching, batch processing, long-context rates, tokenizer differences, tool fees and data residency. A seventh, low-latency processing, can double the per-token price.
Prompt caching. Both providers charge less for input they have already seen. Anthropic bills a cache write at 1.25x the base input price for a 5-minute cache or 2x for a 1-hour cache, and a cache read at 0.05x on Claude Opus 5.5 and Claude Sonnet 5.5 and 0.025x on Claude Fable 5.1.
OpenAI lists its own cached-input price per model, with cache writes priced for 30-minute and 12-hour durations.
At the balanced tier the cache-read prices match: $0.10 per million on both Claude Sonnet 5.5 and gpt-6.1-sol. At the premium tier they do not: $0.25 on Claude Fable 5.1 against $1.00 on gpt-6-astra. On the medium workload with 80% of input served from cache (cache-write cost excluded), Claude Fable 5.1 comes to $1,220 and gpt-6-astra to $1,280.
Batch processing. Anthropic's Batch API gives "a 50 percent discount on both input and output tokens." OpenAI's Batch prices are also half of standard, and its Flex tier lists the same prices as Batch. The medium balanced workload drops from $400 to $200 on either side if the work can wait. Anthropic states that its caching discounts stack with the Batch discount.
Long context. This is where the providers differ most. Anthropic says Claude 4.6 and later models, except Claude Haiku 5.5, include the full 1M-token context window at standard pricing. OpenAI charges a higher long-context rate once input passes 272K tokens: gpt-6.1-sol moves to $4.00/$15.00 and gpt-6-astra to $20.00/$75.00.
In practice: a medium workload made entirely of 300K-token prompts costs $400 on Claude Sonnet 5.5 and $700 on gpt-6.1-sol. The budget tier flips the other way. Claude Haiku 5.5 moves to $0.50/$2.50 once a prompt passes 100,000 tokens, while gpt-6-luna stays at $0.10/$0.50 up to 272K.
Tokenizer differences. Prices are per token, and the two providers do not split text into tokens the same way, so the same document can be a different number of billable tokens on each.
Anthropic states that Claude 4.7 and later models use a newer tokenizer that produces approximately 30% more tokens for the same text than its previous tokenizer. That is a comparison with older Claude models, not with OpenAI; neither provider publishes a cross-provider figure, so measure it on your own prompts.
Web search and tools. Both providers charge for tool calls on top of token costs, and the fee schedules differ by tool.
| Provider | Web search | Other tools |
| Anthropic | $10 per 1,000 web searches plus standard token costs | Web fetch: no charge beyond tokens. Code execution: 1,550 free hours per organization per month, then $0.05 per hour per container |
| OpenAI | $10.00 per 1,000 web search calls plus search content tokens | File search: $2.50 per 1,000 calls plus $0.10 per GB per day of storage (1 GB free). Containers: from $0.03 per 20 minutes |
Tool definitions also cost tokens: Anthropic lists a 286-token tool-use system prompt on Claude Opus 5.5, Claude Sonnet 5.5 and Claude Haiku 5.5.
Data residency. Keeping inference in a specific region costs more on both. Anthropic applies a 1.1x multiplier when you set US-only inference on Claude 4.6 and later models. OpenAI charges a 10% uplift on regional processing endpoints for models released on or after March 5, 2026, and on FedRAMP endpoints starting November 1, 2026. The medium balanced workload goes from $400 to $440 on either side.
Low-latency modes. Both providers sell low-latency processing modes at a multiple of standard pricing. OpenAI lists gpt-6.1-sol at $4.00/$20.00 in that mode, double its standard price, and Anthropic lists Claude Opus 5.5 at $8/$40 in its equivalent mode, which cannot be combined with the Batch API.
How finance teams should budget and track LLM API spend
Per-token pricing makes this a usage bill, not a subscription. That means the budget lives in three places: the provider consoles, your team structure and the monthly close.
1. Set a spend limit in each provider console. Anthropic caps monthly spend by usage tier (Start $500, Build $1,000, Scale $200,000; the Custom tier has no cap), and you can set your own lower limit on the Billing page in the Claude Console. When it is reached, API requests are paused until 00:00 UTC on the first of the next month.
OpenAI separates spend alerts, which notify while traffic continues, from hard spend limits, which stop requests. It also notes that limit enforcement lags behind usage, so recorded spend can run slightly past a hard limit. Set the limit below the number you actually need to hold.
2. Give each team its own workspace or project. Anthropic lets you set custom spend and rate limits per Workspace, though not on the default Workspace. OpenAI applies hard limits at the organization or project level. A separate workspace or project per product team turns one invoice line into spend you can attribute to an owner.
3. Reconcile each provider's charges every month. Anthropic bills on actual monthly usage, and OpenAI's spend limits run on a monthly cycle. Match each invoice against the usage dashboard in the console, by workspace or project, and flag any month where cache hit rates drop or long-context requests spike, since those move the bill without any change in traffic.
If you run several models across both providers, LLM gateways and routers exist that put multiple providers behind one interface; they change where usage is tracked, not the underlying per-token prices above. For the wider framework of owners, budgets and controls, see this guide to AI spend management for startups.
The payment side is a separate layer from the token side. Finance teams can pay AI vendors with Rho corporate cards or Bill Pay, restrict a card to specific merchants or merchant categories so purchases outside them are declined, and sync transactions to accounting software such as NetSuite, QuickBooks Online and Sage Intacct. Token-level usage still lives in each provider's console. Explore the Rho Card.